MONTPELIER — About 9,500 people who rely on public bus service in Vermont’s largest county could be without a ride Monday if the drivers and the agency they work for don’t reach a contract agreement this weekend.

Almost 70 drivers of the Chittenden County Transportation Authority are set to go on strike if an agreement can’t be reached by Monday. The next negotiation session is scheduled for Saturday.

Both the authority and the union say the two sides disagree over working conditions, the hiring of part-time drivers, and working hours.

“We don’t want to go on strike,” driver Rob Slingerland said. “What we want is a fair contract, and that’s what we’re working for.”

The company issued a statement Thursday warning riders that a strike loomed and that if an agreement isn’t reached by Monday, the buses won’t run.

General Manager Bill Watterson said an 11th hour agreement was reached previously in the drivers’ three-year contract that expired in June, and he’s hopeful that will happen again.

“The talk about a possible work stoppage has gotten people understandably concerned,” Watterson said. “The decision on whether there’s going to be a work stoppage is in the hands of the drivers’ union. What we want is to get to the bargaining table and sit down and reach an agreement with the drivers’ union and not have to have any disruption to our service.”

The authority is legally considered a municipality, and was chartered by the Legislature in 1973. It is governed by a 13-member board of commissioners.